Loud speaker



Nov 20, 1928. 1,692,762

C. W. PETERSON LOUD SPEAKER Filed Dec. 30, 1925 INVENTORL mwfm ATTORNEYS Patented Nov. 20, 1928.

CHARLES W. PETERSON,

F DETROIT, MICHIGAN.

' LOUD SPEAKER.

Application filed December 30, 19 25. Serial No. 78,287.

My invention relates to loud speaker horns of a type wherein a diaphragm offragile mate'rial such as parchment paper is used, as the sound reproducing as well as the sound projecting medium.

The use of the conical shaped large area diaphragm for loud speakers has been well developed in recent years and irrespective of the mode or mounting the cone, whether it be bound rigidly, held resiliently, or held by an aperiodic substance at the rim, the practice has generally been to support the dia phragm in such a Way as to be open to the air both front and back.

According to my invention the cone is suported freely in the air, and the improvement imparted by me, lies in the mode of mounting the cone while protecting it at the forward or convex face by suitable members forming part of the mounting device.

It is my object to make an inexpensive and yet fully satisfactory device for this purpose,

' and to the end of fully describing a typical exam 1e of my invention, I give the following description of parts and the arrangement thereof, and append claims relating to the novtlt inherenttherein. 1

In the drawing:

Figure '1 is a front elevation of one of my devices.

Figure 2 is a section taken through the cone retaining and guarding device on the line 2-2 of Figure 1.

Figure 3 is a detail section of the joint closii'f' element taken along lines 3-3 in Fig. 1.

l igure 4 is a plan view of the cone retaining and guarding device.

The particular desi of the cone retaining and guarding device orms no part of my invention. I have shown a split ring 1, from the interior portions of which the metal is formed into arms 2, and are connected together at an apex 3,thereb forming a conical shaped spidel, bounde by a split ring. This device can be made by stamping and forming from a sheet of metal and can have as many spider arms and be given whatever decorative shape as may be found desirable, provided the cortical diaphra m is not enclosed against free access to t e air.

The conical diaphragm is shown at 4, and I have indigated at 5 a connection at the apex of the diaphragm with a wire 6 actuated by a loud speaker receiver. In the completed device the receiver will lie within the space bounded by the interior or concave face of the diaphragm.

As a mounting device I have illustrated a base 7, from which extends a pedestal 8. The ring 9 is secured to the pedestal and is faced on the front face with a felt band 10.

This ring is curled over partially as indicated at 11, and the rim of the ring 1 is also turned over so that it will snap intothe r ng 9, and remain permanently in place until positively withdrawn by prying it out.

p The inner face of the ring element 1 is also faced with a felt strip, as it 12, and the cone dia bragm is so mounted that its periphery ms in contactwith the felt 10, and barely touches the felt 12. This leaves the diaphragm in condition to oscillate as a 2 whole, without having anything but a loose and'aperiodic mounting at the periphery. The cone-shaped" diaphragm is of such shape with relation to the arms 2 that it does not touch them at any point, and the spacing between the armsis not sufficient to dim the sound emanating frdm the cone upon oscillation thereof.

Should the device he dropped the arms will protect the cone from'breakage on one s de, and the -mounting of the receiver will ,provide the protection on the other. e

In order to assure thatthe retainer will stay inplace in the outer or supported ring, I provide a conical nut 20, whichis held in place and spreading the meeting edges of the split ring 1, by means of a screw 21, held in a washer 22, that abuts the ring, and straddles and conceals the line of split. The washer 22 may also have a tongue 23, which engages a notch in the conical nut 20 and prevents the nut from slipping as the screw is tightened down.

Having thus described my invention, what I claim as new and desire to secure by Let-' ters Patent, is

1. In a loud speaker, a cone diaphragm supported in free access to air, a supported ring for mounting the diaphragm, and a ring detachable from the supported ring, and having a conical spider of arms tapering, to a center,1so' as to surround but not touch th'e convex face of the cone.

2. In a loud speaker, a cone diaphragm supported infree access to air, a supported ring for mounting the diaphragm, and a ring detachable from the supported ring, and having a conical spider of arms tapering to a center, so as to surround but not touch the convex face of the cone, said ring being split, and shaped to snap into the supported rm 3 In a loud speaker, a cone diaphragm supported in free access to air, a supporting ring for mounting said diaphragm,

and a matching ring secured to the supporting ring, and having an open Work projecting body, arranged to house but not contact with the cone diaphragm.

4. In a loud speaker, a cone diaphragm supported in free access to air, a mounting means comprising a supported element, and

an element attached thereto, between which 15 ring in which said diaphragm is mounted,

and means projecting in the form of a protecting grid about the convex portion of the cone and secured to said ring, said means being out of contact with the cone.

CHARLES V. PETERSON. 

